The prevalence and distribution of medial arterial calcification was assessed in the feet of four subject groups; 54 neuropathic diabetic patients with previous foot ulceration (U), median age 60.5 (50.5-67 interquartile range) years, duration of diabetes 19.5 (9.9-29.9) years; 40 neuropathic diabetic patients without a foot ulcer history (N), age 68 (62-73) years, duration of diabetes 14.0 (8.0-28.0) years; 43 non-neuropathic diabetic patients (NN), age 60.5 (52-68.5) years, duration of diabetes 14.0 (8.0-28.0) years and 50 non-diabetic control subjects, age 62.5 (53.7-70) years. A single radiologist graded medial arterial calcification as absent, mild or severe, at the ankle, hind-foot, mid-foot, metatarsals and toes on standardised plain lateral and antero-posterior foot radiographs taken by a single radiographer. Diabetes history, vibration perception threshold, ankle systolic pressure and serum creatinine were also assessed. Medial arterial calcification was significantly greater (total score 18 [3-31]) in neuropathic diabetic patients with previous ulceration (U vs N p < 0.01, U vs NN p < 0.001). Non-neuropathic diabetic patients did not have significantly higher arterial calcification scores than age-matched non-diabetic control subjects. Medial arterial calcification correlated with vibration perception threshold (r = 0.35), duration of diabetes (r = 0.32) and serum creatinine (r = 0.41), (all p < 0.01). Logistic regression models showed vibration perception and duration of diabetes to predict the probability of any calcification. Serum creatinine level was added to predict severe calcification.(ABSTRACT TRUNCATED AT 250 WORDS)